Hydroxy-thionaphthenes containing alpha pyrazole ring



Patented Sept. 13, 1932 RICHARD HERZ, 0F FRANKFORT-ON-THE-MAIN, Ann Max SCHUBEB'I" AND WALTER GENERAL ANILINE womzs; INQ, WARE No Drawing. Application filed. Becember19,

Our present invention relates to new hy- I droXy-thionaphthenes containing a pyrazole ring, more particularly it relates to hydroxy-thionaphthene compounds which probably correspond to the general formula:

on o HN/ onn on wherein the CH-group stands in para-position to the G-OH-group and the benzene as well as the pyrazole nucleus maycontain alkyl-groups.

These compounds are produced, for in stance, in the following manner; 1

A B-amino-indazole compound corresponding probably to the formula:

wherein one of the positions designated by X is unoccupied and the benzene as well as the pyrazole nucleus may contain alkylgroups, is converted into the corresponding ortho-mercaptan, the SH-group standing in one of the positions indicated by X, for instance, by treating the starting material with a sulfocyanide and a halogen and splitting up the sulfocyanic group thus introduced (compare the proc- P esses disclosed in the U. S. Patents No. 1,790, added and the mass is boiled for half an hour n 097, No. 1,784,441, and No. 1,788,297). This mercaptan is condensed with mono-chloroacetic acid to form the corresponding thioglycollic acid and this acid istransformed in the known manner into the hydroXy-thionaphthene compound. Or the sulfate of a G-amino-indazole is transformed to the orthosulfonic acid by intramolecular rearrangement, the sulfonic group is converted into the corresponding acid chloride group which yields on reduction the mercapto-group, and

DELA

HYDROXY-THIONAIEI-ITHENES CONTAINING- A IEYRAZOLE RING;

1929, Seria1 No. 415,351, and in Germany December 22, 192 8;

the mercaptan is transformed into the thioglycollic acid, for instance, in the manner described in U. S. Application Serial No. 262; 038, filed March 15, 1928.

' The pyrazole-hydroxy thus obtained are insoluble in water, easily soluble in dilute caustic alkali solutions without an addition of organic solvents.

In order to further illustrate our invention the following'examples are given, .the parts being by weight and all temperatures in centigrade degrees, but it is understood, that our invention is not .limited to the particular products of reacting conditions mentioned therein 7 v 7 Example 1 A. solution of 7 0 parts of G-a'mino-indazole (melting point 210, described by Witt, Nolting and Grandmougin in Berichte der deutschen chemischen Gesellschaft, vol. 23 (1890) ,page 3635) in 1,000 parts of methanol is mixed with 150 parts of ammonium sulfocyanide. Then a solution of 85 parts of bromine in 300 parts of methanol is allowed to run in while stirring. Ortho-sulfocyanogenoaminorindazole precipitates in the form of colorless leaflets not yet melting at 300, which are filtered and dried.

34 indazole thus obtained are boiled with 200 parts of ethyl-alcohol and parts of a caustic soda solution of 40% strength. Then 5 arts of zinc dust and 100 parts of water are under a reflux condenser. After cooling to 50 the reaction mass is condensed with 15 parts of mono-chloro-acetic acid. Then the alcohol is distilled ofi and the remaining solution is filtered. By acidifying with strong hydrochloric acid G-amiho-indazole-orthothioglycollic acid anhydride precipitates.

- thionaphthenes parts of ortho-sulfocyanogeno-amino- BRUNNER, 0F FRANKFORT-ON-THE-MAIN-FECHENHEIM, GERMANY, ASSIGNOBS TO OF NEW YORK, N. Y., A CORPORATION OF This compound represents colorless needles melting above 300.

44 parts of this anhydride are boiled for 6 hours under a reflux condenser with a solution of 35 parts of caustic soda in 400 parts of water. The clear solution is mixed with a solution of 21 parts of sodium nitrite in 300 parts of water and the mixture is introduced at 0 into 150 parts of hydrochloric acid 20 B and 200 parts of ice. The clear diazo-solution is allowed to run at 304[0 into a solution of complex copper cyanide corresponding to 60 parts of sodium cyanide with a simultaneous addition of 100 parts of sodium bicarbonate. When the capacity of being diazotized has disappeared the mass is acidified. The precipitated 6-cyanogeno-indazole-ortho-thioglycollic acid is filtered, washed and dried.

26 parts of the raw cyanogeno-indazolethioglycollic acid are heated to 8090 for 8 hours with a solution of 73 parts of crystallized sodium sulfide in 31 parts of water. Then the mass is dissolved in water, filtered and acidified. The precipitated amino-pyrazole-thionaphthene-carboxylic acid is filtered off and washed. The formation of this compound takes place by an intramolecular rearrangement, probable according to one of the following equations:

The moist paste of this carboxylic acid corresponding to 20 parts of the dry substance is warmed to 9095 for 3 hours with a solution of parts of concentrated sulfuric acid in 3000 parts of water. After cooling the formed hydroXy-pyrazole-thionaphthene is filtered off and dried. It represents yellow needles melting at 235. This step of the reaction probably takes place according to one of the following equations:

Example 2 6-amino-2-methylindazole of the probable formula on HaO-N l N NH2 Ewamgvle 3 5-methyl-6-nitro-indazole of the probable formula OH on HN a N. N O 2 which is described by Nolting in Berichte der deutschen chemischen Gesellschaft, Vol. 37 (1904), page 2588, is reduced by means iron and acetic acid to form 5-methyl-6-amino indazole. This amino-compound represents colorless needles melting at 240-242 and corresponds probably to the formula:

$H OH: HN

N NHz It is treated with /OH HaC-N or 0-011 ammonium sulfocyanide and bromide in the presence of glacial acetic acid. Thereby 5-methyl-6-amino-7-sulfocyanogeno-indazole is obtained. It forms when recrystallized from butanol colorless and corresponds The sulfocyanogeno compounds yields when boiled with a caustic potash solution 5- methyl-6-amino-7-mercapto-indazole of the probable formula:

H v The mercaptan is condensed with monochloro-acetic acid. The 5-methyl-6-aminoindazole-7-thioglycollic acid thus formed corresponds probably to the formula:

Its anhydride forms colorless prisms melting above 800. This thioglycollic acid yields when condensed in the manner escribed above a hydroXy-thionaphthene compound of the probable formula:

which forms when recrystallized from monochloro-benzene, yellow leaflets melting at 285.

We claim:

1. Asnew products, the hydroxy-pyrazole thionaphthenes probably corresponding to the general formula:

OH S OH HN CH or HN which compound forms yellow needles, melting at 235 C., is insoluble in water, easily soluble in dilute caustic alkali solutions even without an addition of organic solvents, and. yields when oxidized a grey thioindigo dyestuff.

3. As a new product, the hydroxy-pyrazole-thionaphthene probably corresponding to one of the following formulae:

'11 which compound has a melting point of 200 C., is insoluble in water but easily soluble in dilute caustic alkali solutions even without an addition of organic solvents.

4. As a new product, the hydroxy-pyra zole-thionaphthen-e probably corresponding to the formula:

--ti-on which compound forms yellow leaflets melting at 285 0., is insoluble in water but easily soluble in dilute caustic alkali solutions even without an addition of organic solvents.

In testimony whereof, we aflix our signatures.

RICHARD HERZ. MAX SGHUBERT. WALTER BRUNNER.

Certificate of Correction Patent No. 1,87 6,930. September 13, 1932. RICHARD HERZ, ET AL.

It is hereby certified that error appears in the printed specification of the abovenumbered patent requiring correction as follows: Page 2, at line 35, strike out the left-hand formula, and insert instead the formula shown below:

and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 16th day of May, A. D; 1933.

[SEAL] M. J. MOORE,

Acting Gammz'ssz'oner of Patents. 

